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The consequences of pumping on food quality are poorly understood, and wine is a good example. Therefore, the present paper examines the use of four pumps and the application of inertization on wine quality. We develop a novel, physical qualitative index (PQI), which is the ratio between pumping specific energy and the net positive suction head, and examine the correlation with wine quality characteristics. Four pumps (a flexible impeller pump, a lobe pump, a peristaltic pump, and a rotary piston pump) that are widely-used in wine cellars were compared over a wide array of chemical-physical variables, during conventional racking, with and without inertization. The analysis found a correlation between the PQI and some quality variables, and this finding was confirmed by a conventional statistical analysis (ANOVA-GLM). Overall, the flexible impeller pump performed slightly differently compared to the other pumps with respect to some color-related parameters. All pumps behave differently as a function of inertization (or not). Inertization was effective in minimizing volatile losses.

This study examined the influence of ground coffee granulometry and particle distribution on extraction parameters. They have been investigated the physicochemical properties, and the bioactive and volatile compound content in coffee obtained by a conventional filter method, the French Press, as a function of particle size and distribution. Some samples have been used for the extraction the directly the grinding machine, set at different grinding grade, and other samples have been seed before the usage in order to reproduce samples at different particle size class very homogeneous. The results showed that bioactive and volatile compounds are released differently in the beverages depending on the specific particle size. The results have been demonstrated that a homogeneous grind was more deficient in bioactive compounds and total dissolved solids than a classical, bimodal grind. Moreover, extraction from a very fine homogeneous grind was poorest with respect to these compounds, despite the greater surface in contact with the solvent. Conversely, bimodal grinds obtained conventional by the grinding machine, which were more heterogeneous from a granulometric point of view, were found to be richer in volatile organic and bioactive compounds. The study highlights that the grind plays a key role in producing well-extracted coffee and, therefore, in making the most of the potential inherent in the roasted bean.

The present study aimed to model the kinetics of factors involved in wine aging to highlight the effects caused by different tank materials. It is known that materials affect wine composition through releasing of tannins, elementals and allowing different level of oxygen permeation. To monitor how the composition of a red wine was influenced by the contact with different kind of material, a Sangiovese red wine from the 2018 harvest was aged for one-year simultaneously in six different 5 hL tank materials including stainless steel, epoxy-coated concrete, uncoated concrete, raw earthenware, new and used oak wood. The registered differences were described through kinetic modeling of some wine’s chemical and physical parameters. In particular, the one-year evolution of the dissolved oxygen, redox potential and phenolic composition of the wines showed significant differences according to the tank material. Like the oak barrels, the raw earthenware amphorae and uncoated concrete tanks enhanced the polymerisation of the phenolic fraction of the wine. Instead, the stainless steel and epoxy-coated concrete proved to be the most chemically inert materials as they showed the least variability of redox potential and the lowest degree of color evolution.

Coffee powder is obtained with a grinding machine. Espresso coffee is prepared when hot water is forced under pressure through the puck of coffee powder, and the optimal espresso flow rate is 1 g s−1. However, this flow rate can change for different extractions, forcing baristas to frequently change the setup of the grinder. Grinding grade is one of the most important sources of variation in the quality of espresso. This study tests an innovative method to prepare coffee powder puck, designed to reduce variability in flow rate between extractions. The method is based on stratified layers of ground coffee with different granulometry, and it was tested in three trials with different coffees and grinders. The flow rate associated with the new method (Patent WO/2020/148258- PCT/EP2020/050773) was more stable than the rate in a conventional system, reliability was optimized by placing larger coffee particles at the bottom, and finer particles at the top of the filter basket.

Recent years have seen a growing awareness of the need to reduce waste and protect the environment. During the preparation of a coffee beverage, large amounts of a solid residue known as spent coffee grounds (SCG) are produced. This study investigates the recovery of phytochemicals from SCG. The aim is to estimate the effect of a wide number variables on the amount of caffeine and phytochemicals recovered with a green method for water-soluble compounds that does not require the use of organic solvents. In the first part, we use a Plackett–Burman design to estimate which extraction parameters have most influence on phytochemical recovery. In the second part, we test only the significant factors and caffeine and chlorogenic acids were quantified using HPLC-DAD. The first part of the study showed that the temperature and the type of SCG can significantlyaffect the phytochemical recovery. In the second part, four temperatures and two types of SCG were tested and thehigher concentrations of caffeine and chlorogenic acids were found at 110 °C. Furthermore, a significant effect was found for type of SCG with significantly higher phytochemical recovery for the French Press compared to the Espresso method. The mild temperature, combined with the use of water as a solvent make the recovery system both green and low-cost.

This study evaluates the effect of filter press filtration on the shelf life of extra virgin olive oil (EVOO). Olives were harvested and processed on the same day by a continuous industrial plant equipped with a hammer crusher, a vertical malaxator, and a decanter. One part of the oil obtained was bottled in 0.5 liter dark‐green bottles with headspace representing a quarter of the bottle's volume (cloudy oil). The other part was filtered (using a filter press) directly after decanting and manually bottled using the same procedure (filtered oil). All samples were stored in a purpose‐built chamber and periodically analyzed. Samples were characterized by their water content, free acidity, peroxide value, specific extinction coefficients (K232 and K268), total chlorophyll, tocopherols, total phenolic compounds, HPLC phenolic profile, volatile compounds, fatty acid composition, and sensory analysis. Immediately after filtration, the only differences that could be detected were related to turbidity and total solids. In the subsequent analyses, filtered oil retained superior nutritional and sensory characteristics than cloudy oil. More importantly, the filtered oil remained at the standard required for categorization as “extra‐virgin olive oil” for longer. Practical applications: The article describes the effect of the filtration without vertical centrifugation on the olive oil quality. Shelf life tests have been performed to evaluate the changes in chemical and sensorial properties of olive oils. Since the filtration and its timing is controversial in the literature, a complete investigation, which considers the storage, is required. Furthermore, this is, to the best of authors knowledge, the first study focusing on the changes of oils produced without vertical centrifuge. This study evaluates the effect of filter press filtration on the shelf life of extra virgin olive oil (EVOO). Olives were harvested and processed on the same day by a continuous industrial plant equipped with a hammer crusher, a vertical malaxator, and a decanter. One part of the oil obtained was bottled (cloudy oil). The other part was filtered (using a filter press) directly after decanting and manually bottled using the same procedure (filtered oil). All samples were stored in a purpose‐built chamber and periodically analyzed. The results show a less degraded phenolic fraction in the filtered olive oils. In fact, compounds such as Tyrosol and Hydroxytyrosol, which are the final product of hydrolysis of secoiridoids, remain stable in filtered oils and increase in cloudy. Moreover, filtered olive oils have a better sensory profile than the cloudy along the shelf life. These data are confirmed by the GC‐MS analysis. The results confirm that filtration is essential in order to maintain the nutritional characteristics of the oil, and slow the onset of the main defects.

The grape harvest period and applied methods determine the levels of unripe berries (substandard berries, SSB) and material other than grape (MOG) in grape must. This study describes, in a full-factorial experiment at the industrial scale, the impact of different levels of MOG and SSB on the chemical composition and the sensorial properties of Sangiovese wines. The addition to the grape juice of 30 g/kg MOG led to significant changes in chemical composition, altering key components such as titratable acidity, lactic acid level, flavonoids concentration and color-related parameters. Sensorial parameters were also modified, as demonstrated by statistically significant differences both in astringency and in the concentration of volatile organic compounds. The threshold level for unripe (SSB) berries was arbitrarily defined as below 21.5 °Bx. In the experimental vineyard used here, 19–36% of grapes were unripe, depending on the harvest zone. The level of SSB influenced some important chemical and sensorial characteristics. Changes in SSB content altered ethanol concentration, titratable acidity, malic and lactic acid levels, a range of polyphenol-related parameters, certain volatile organic compound concentrations, as well as color and bitterness.

Each region of the world has its own methods, protocols, instruments and procedures regarding how to brew coffee. The final result in the cup is strongly affected by the extraction method, and many studies have focused on this subject. However, few studies have investigated slow, cold extraction methods, despite their popularity among baristas. Therefore, the present study aimed to characterize and compare two cold extraction methods: cold brew and cold drip. RESULTS Physical and chemical analyses were used to describe coffee beverages in terms of pH, total solids, refractive index, density and viscosity. Caffeine and cinnamic acids were quantified using high-performance liquid chromatography (HPLC)/diode array detector and HPLC/mass spectrometry. A sensory evaluation included aroma, flavor and textural attributes. CONCLUSIONS Significant differences were found in the chemical and physical parameters, both between and within the two methods, as a function of the extraction temperature and contact time. Similarly, the sensory evaluation found differences in flavor profiles, as measured in terms of bitterness, sweetness, sourness and global intensity. ? 2018 Society of Chemical Industry

Crushing speed can be used to characterize olive oils. Faster crushing significantly increases chlorophyll, total biophenol, 3,4‐DHPEA‐EDA, and p‐DHPEA‐EDA. Panel testing found higher bitterness and astringency scores in oils produced at the higher speed.

In olive oil production, olive paste is fed into a decanter in order to separate the oil from solids. The decanter is usually fed by a mohno or lobe pump. In this study, we analyze the composition of olive paste and pomace at the beginning, middle, and end of decanter feeding. The results show a change in paste composition with the two types of pumps. In both cases, olive paste contains a higher percentage of water and oil at the beginning of decanter feeding than at the end. This phenomenon is probably related to the different viscosity of the three components in the system. Furthermore, as the level for the recovery of olive oil is fixed, the change in the solid/liquid ratio causes product loss. This loss is demonstrated and quantified through the measurement of pomace oil content. Practical Applications: The paper quantifies the effect of the olive paste transport from malaxers to decanter on the olive oil yield. The transport causes a change in the relative composition among oil, water, and solids. The decanter centrifuge is not able to separate efficiently paste with different compositions. This causes marked product losses. The presented data could lead to the development of a control system able to limit the losses. In this study the ratio of solids, water and oil in the olive paste at the beginning, middle, and end of decanter feeding are tested. Change in paste composition with the two types of pumps. Olive paste contains a higher percentage of water and oil at the beginning of decanter feeding than at the end. The level for the recovery of oil is fixed and the change in the ratio causes product loss that is quantified through the measurement of pomace oil content.

The stripping treatment of extra virgin olive oil (EVOO) by nitrogen gas to remove dissolved oxygen (DO) was tested immediately after the oil production. Dissolved oxygen was measured before and after stripping, as well as one week later along with chemical analyses with the aim to assess the effects of the stripping treatment on EVOO quality. Stripping gave a great reduction of DO, of ca 50%. Both stripped (SO) and non-stripped (non-SO) oil samples showed a fast DO consumption up to zero in seven days. At this time, the non-SO samples showed significant higher peroxide value probably as a consequence of the initial higher DO concentration that gives a greater formation of free radicals. A slightly lower concentration of total phenols was recorded for SO samples. A slight but significant decrease was recorded for only (E)-hex-2-enal concentration within the volatile compounds.

The relationship between olive paste malaxation temperature and the concentration of olive oil hydrophilic phenols (HP), i.e. simple phenols, secoiridoids and lignans, was investigated. Malaxation experiments were performed at laboratory scale for 45 min at 21, 24, 27, 30, 33 and 36 °C. A significant (p

The influence of the olive oil processing steps [paste malaxation (PM), decanter centrifugation (DC), and vertical centrifugation (VC)] on the dissolved oxygen (DO) concentration in virgin olive oil (VOO) right after production was investigated at industrial plant scale for two successive years. The influence of this parameter on quality decay during shelf life, assessed by peroxide value (PV) analysis, was also monitored. The VC step showed the higher oxygenation effect (50% increase in comparison to the control), and a good linear regression (r 2 = 0.83) was found between the initial DO concentration and the PV after 2 days. An 18-months shelf life test, performed on VOO sampled before and after the VC, indicated the slowest decay kinetics in the oils with the lower initial DO concentration, i.e. the non-centrifuged oils.

The effect of blanketing with CO2, naturally evolved during malaxation of olive pastes, on the quality of virgin olive oil was investigated at lab-scale. The O2 depletion was monitored along with CO2 emission to confirm the previously hypothesized accelerated respiration. Malaxation experiments were conducted for 180 min both in sealed (SC) and in the traditional open-to-air conditions to ascertain whether the oil quality was affected by O2 concentration as afforded by CO2 blanketing. The quality of olive oils obtained at different time intervals was monitored by total acidity, peroxide value (PV), specific extinction coefficients K232 and K270, total chlorophyll and total hydrophilic phenols, and HPLC hydrophilic phenols profile. A rapid decrease in oxygen concentration and a simultaneous increase in CO2 concentration were recorded, confirming the accelerated respiration. The oil produced in SC showed a lower PV and K232 coefficient and a higher chlorophyll (10–17 mg/kg) and hydrophilic phenols (110 mg/kg) concentration. No differences in total acidity and K270 coefficient were observed. The hydrophilic phenols profile indicated that, at least for the Frantoio cultivar and an advanced ripeness state, the maximal extraction is generally achieved already after 20 min. Most of the individual hydrophilic phenols have higher concentrations (up to 50%) in SC.

The emission of carbon dioxide (CO2) from olive paste during malaxation was investigated in a lab experiment using a hermetically sealed malaxation chamber. A rapid increase in the concentration of CO2 during malaxation was observed, with an average increase of 32 ml/(l min) for the initial 5 min. Then, the emission progressively decreased to a mean rate of 1.1 ml/(l min). This was probably the result of an initial acceleration in respiration followed by the gradual onset of fermentation processes as ambient oxygen was depleted. After malaxation, small amounts of cellular fermentation products (e.g. ethanol and lactic acid) were detected in the wastewater. In order to examine this phenomenon of the inhibition of oxidation due to evolved CO2, malaxation experiments were conducted in both a sealed and an open-air mixing apparatus. The differences in chlorophyll concentration of the resulting oils were then measured. Large amounts of chlorophyll, about twice as much, were found in the oil produced under sealed conditions. This increase in the concentration of chlorophyll resulted from the limited oxidation of the sample by atmospheric oxygen due to the protection of the evolved CO2.

Pre-fermentation cold maceration of must by the direct addition of two cryogens was studied. The experiments were conducted on Sangiovese grape from a typical Chianti vineyard in the year 2001 with two cryogens (solid state carbon dioxide and liquid nitrogen) and at various temperatures (from −5 to +5 °C) in 500-L batches for 48 h. The wines obtained were characterized by chemical analyses and sensory evaluation, and higher quality resulted as seen from the analytical and sensory characteristics with higher extraction of polyphenolic compounds at lower cold maceration temperature. Liquid nitrogen was more effective than solid carbon dioxide at the same temperature. Proportional increase of wine quality with lower cold maceration temperature was observed for solid carbon dioxide. Further investigation is needed to establish the management protocol, a proper engineering of this technique, and to evaluate its economical advantages.

This study compared two harvesting techniques (manual and mechanical) and three grape sorting methods (no sorting, manual, and densimetric) in attempts to obtain high-quality must. The trials were carried out in 2009 and 2010 in Tuscany, Italy. The effectiveness of the harvest-sorting chain was assessed on two parameters. Substandard berries (SSB) is the percentage of berries, which do not meet quality standards that enter the winemaking process, and material other than grape (MOG) is a measure of the cleanliness of the berries entering the process. In the two years the trial was run the grape maturation level was widely different; in 2009 the vintage was more far mature than in 2010. With respect to SSB content and harvesting methods, in 2009 (more mature grapes) hand-picking reduced SSB content, while in 2010 there were no differences between the two harvesting methods. In both years, densimetric sorting reduced SSB content, while there were no significant differences between no sorting and manual sorting. In terms of MOG content, both harvesting and sorting results were inconsistent. In 2009, MOG was lower in mechanically harvested grapes; while in 2010 it was lower in hand-picked grapes. As for sorting methods, in 2009 there were no differences in MOG, while in 2010 mechanical sorting produced better results. Our results question whether the post-harvest sorting techniques used by many estates are effective; particularly as the question has received little attention and no previous research has compared methods. Secondly, our study contributes to the debate on the effects of harvesting technique on wine quality.

Virgin olive oil vertical centrifugation under inert gas (IVC) was compared with conventional vertical centrifugation in contact with air (CVC). IVC gives a strong reduction of the oil oxygenation in terms of reduced dissolved oxygen concentration and oxidative indexes (peroxide values and K232). Minor compounds (chlorophyll and total phenols) and volatile compounds were not affected by the treatment. Practical applications: A technical implementation of inertized vertical separators appears a practicable solution to preserve virgin olive oil quality traits. This can be easily implemented both by the mill owner with homemade adjustment of the existing machines and by plant industrial manufacturers.